Moetimee



(No Model.)

M. O. OOGSWELL.

GRINDING MILL.

No. 324,363. Patented Alig. 18,1885.

UNITED STATES PATENT ()FFICE.

MORTIMER C. GOGSWELL, OF NEW YORK, N. Y.

GRINDING-MILL.

SPECIFICATION forming part of Letters Patent No. 324,363, dated August18, 1885.

Application filed August 25, 1884. (No model.)

To all whom it may concern.-

Be it known that I, MORTIMER G. CoGsWELL, of the city of New York, inthe county and State of New York, and a citizen of the United States ofAmerica, have invented an Improvement in Grinding-Mills, of which thefollowing is a specification, reference being had to the accompanyingdrawings, forming part of the same, in which Figure 1 is a verticalcentral longitudinal section of a grindingmill containing my invention,and Figs. 2 and 3 are face views of the grinding-disks forming a part ofsaid mill.

A and A are two horizontal shafts mounted in line with each other torotate in suitable bearing-boxes, B B B B supported on stand ardsresting on a suitable bed plate or frame. Each shaft is provided with adriving-pulley, O G. On the inner ends of thesaid shafts are fixed thegrinding-disks D D. These disks are inclosed in a case, F, Within whichthey may freely revolve, said case being provided with a centralopening, a, for the introduction of grain and air into the mill througha large central opening, a, in the disk D. The channeled or ribbedgrinding-surfaces may, if preferred, be'formed on separate plates,E,secured to the said disks in any suitable way.

G is a spout for conducting the grain from a shoe, H, to the opening ain the case F. The air as well as the grain passes through this openingand the opening a in the disk D into the space between the disks.

In the operation of agrinding-mill thus constructed I have found that adifficulty is experienced in preventing the escape from the case F ofdust or flour through the opening a, which necessarily exists betweenthe hub b of the disk D and the edge of the opening in said case,through which passes and in which rotates the said hub. It isimpracticable, or at least very difficult, to make the joint between thecase and the hub at this aperture so tight as to prevent the passage ofair through it, the air of course under the circumstances carrying withit more or less of dust or flour; and this dust or flour is thrownimmediately upon the shaft A, and finds its way more or less into thebearing or journal box B, and occasions heating of the shaft in thatbearing, as well as loss of flour. To obviate this difficulty, I make asmall opening, d, one or more, through one of the grinding-disks D, nearits hub, through which the air that would in the absence of such openingor openings be forced out through the opening 0 is, by the centrifugalaction of the revolving disks, drawn into the space between them. I findthat these openings d completely prevent the escape of flour and dustfrom the case F through the space 0.

I do not intend here to claim, broadly, in a grindingmill, thecombination of two inclosed opposing grindingdisks made to rotate inopposite directions, provided on their opposing surfaces with radialprojecting ribs,

reserving said broader claim for a separate application which it is myintention to make.

What I claim as my invention, and desire to secure by Letters Patent,is-

In a grinding-mill, the combination, with an inclosing-casing providedwith an opening for the introduction of grain to the .mill, of twoseparate shafts rotating in opposite directions and opposing grindingdisks D D, mounted thereon, one of said disks being provided with anopening for the introduction of grain, and the other having an openingnear its center for the admission of air into the space between thedisks, as and for the purpose specified.

MORTIMER O. OOGSWELL.

Witnesses:

A.'G. N. VERMILYA, D. PALMER HERRIOK.

